The developer of a hotel resisted enforcement of an adjudicator’s decision, claiming that there had been a breach of the rules of natural justice. It said that the adjudicator had failed to deal with certain defences it had put forward. But the developer had previously asked the adjudicator to correct errors in the decision under the slip rule. Was that earlier request fatal to the enforcement challenge?

Yes, said the court. If there are good grounds to object, unless there is an express reservation of rights, either the whole of the relevant decision must be accepted or the whole of it must be contested. The developer had made no such reservation and, by inviting the adjudicator to exercise his powers under the slip rule, it had waived, or elected to abandon, its right to challenge enforcement of the decision, because, in doing so, it had chosen to treat the decision as valid.

Dawnus Construction Holdings Ltd v Marsh Life Ltd [2017] EWHC 1066